arm: corex_m: add byte/half-word sized memory accessors

The byte ones are required for ns16550 uart driver which is
present on some arm socs. Add half-word ones for completeness.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
1 file changed